Conventionally, as an infrared image sensor, thermal detectors for detecting infrared rays using a material whose resistance value varies with temperature are known (see Patent Literatures 1 and 2 for example). The detector described in Patent Literature 1 is what is called a bolometer-type infrared detector, configured such that a plurality of pixels each including a heat sensitive resistor for sensing incident infrared rays are arranged two-dimensionally. This infrared detector is provided with a reference pixel for each of the pixels, and calculates the difference between a signal of each pixel and a signal of each reference pixel to compensate for the influence of environment changes around the infrared detector.
An infrared detector described in Patent Literature 2 is configured such that a plurality of pixels each including a heat sensitive resistance for sensing incident infrared rays are arranged two-dimensionally. This infrared detector is provided with a reference pixel for each column of pixels, and calculates the difference between a signal of each pixel and a signal of each reference pixel to compensate for the temperature rise of diodes due to self-heating when a current is caused to flow to the pixels. In other words, compensation for the self-heating in a plurality of pixels contained in a line of pixels is performed with one reference pixel.